M101: The Pinwheel Galaxy
10.03.2003

Why do many galaxies appear as spirals? A striking example is M101, shown above, whose relatively close distance of about 22 million light years allow it to be studied in some detail. Recent evidence...

Night Lightning on Jupiter
16.12.1997

Why is there lightning on Jupiter? Lightning is a sudden rush of electrically charged particles from one location to another. To create lightning, charges must first separate inside a cloud. On Earth, drafts of colliding ice and water droplets usually create this charge separation, but what happens on Jupiter?

Betelgeuse
19.04.1998

Here is the first direct picture of the surface of a star other than our Sun. Taken by the Hubble Space Telescope in 1995, the atmosphere of Betelgeuse reveals some unexpected features, including a large bright hotspot visible below the center.

A Solar Prominence from SOHO
16.04.2006

How can gas float above the Sun? Twisted magnetic fields arching from the solar surface can trap ionized gas, suspending it in huge looping structures. These majestic plasma arches are seen as prominences above the solar limb.

Comet Between Fireworks and Lightning
5.07.2008

Sometimes the sky itself is the best show in town. Last January, people from Perth, Australia gathered on a local beach to watch a sky light up with delights near and far. Nearby, fireworks exploded as part of Australia Day celebrations. On the far right, lightning from a thunderstorm flashed in the distance.

Geminid Fireball over Mount Balang
16.12.2014

This was a sky to remember. While viewing the Geminids meteor shower a few days ago, a bright fireball was captured over Mt. Balang, China with particularly picturesque surroundings. In the foreground, a sea of light clouds slowly floated between dark mountain peaks.

Cerro Tololo Trails
22.10.2016

Early one moonlit evening car lights left a wandering trail along the road to the Chilean Cerro Tololo Inter-American Observatory. Setting stars left the wandering trails in the sky. The serene view toward the mountainous horizon was captured in a telephoto timelapse image and video taken from nearby Cerro Pachon, home to Gemini South.

The Full Moon and the Dancer
22.01.2022

On Monday, January's Full Moon rose as the Sun set. Spotted near the eastern horizon, its warm hues are seen in this photo taken near Cagliari, capital city of the Italian island of Sardinia.

Saturn Rotates
3.10.2000

The dramatic rotation of the cloud-tops of Saturn every ten-hours is particularly evident from orbit around the gas giant planet. With a good enough telescope, however, such rotation is visible even from Earth, as shown by this time-lapse image sequence from the Hubble Space Telescope taken in November 1990.

In the Center of the Keyhole Nebula
21.07.1997

Stars, like people, do not always go gentle into that good night. The above Keyhole Nebula results from dying star Eta Carinae's violently casting off dust and gas during its final centuries. Eta Carinae is many times more massive than our own Sun, and should eventually undergo a tremendous supernova explosion.